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Work Flow

To ensure correct diagnosis and repair, testing should be done in the following order:

  1. Get detailed information about the conditions and the environment when the incident/symptom occurred using the diagnostic work sheet. See Figure .
  2. Before confirming the concern, check and write down, or print out using CONSULT-II or GST, the (1st trip) DTC and the (1st trip) freeze frame data, then erase the DTC and the data. See RETRIEVING DIAGNOSTIC TROUBLE CODES  . The (1st trip) DTC and the (1st trip) freeze frame data can be used when duplicating the incident at steps  3 and  4 . If the incident cannot be verified, see INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. Study the relationship between the cause, specified by (1st trip) DTC, and the symptom described by the customer. See SYMPTOMS in TROUBLE SHOOTING - NO CODES article. Also check related service bulletins for information.
  3. Try to confirm the symptom and under what conditions the incident occurs. The diagnostic work sheet and the freeze frame data are useful to verify the incident. Connect CONSULT-II to the vehicle in DATA MONITOR (AUTO TRIG) mode and check real time diagnosis results. If the incident cannot be verified, see INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. If the malfunction code is not detected, go to next step. If the malfunction code is detected, skip step No. 4 and perform step  5 .
  4. Try to detect the (1st trip) DTC by driving in or performing the appropriate DTC confirmation procedure. Check and read the (1st trip) DTC and (1st trip) freeze frame data by using CONSULT-II or GST. During the (1st trip) DTC verification, be sure to connect CONSULT-II to the vehicle in DATA MONITOR (AUTO TRIG) mode and check real time diagnosis results. If the incident cannot be verified, see INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. In case the DTC confirmation procedure is not available, perform the overall function check instead. The (1st trip) DTC cannot be displayed by this check, however, this simplified check is an effective alternative. The NG result of the overall function check is the same as the (1st trip) DTC detection.
  5. Take the appropriate action based on the results of steps  1 - 4 . If a DTC is indicated, proceed to appropriate trouble diagnosis for that DTC. If the normal code (P0000)is indicated, proceed to the BASIC DIAGNOSTIC PROCEDURES article and perform basic diagnostic procedures. Then diagnose by symptom. See SYMPTOMS in TROUBLE SHOOTING - NO CODES article.
  6. Identify where to begin diagnosis based on the relationship study between symptom and possible causes. Inspect the system for mechanical binding, loose connectors or wiring damage using appropriate wiring diagrams. See ENGINE PERFORMANCEENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Gently shake the related connectors, components or wiring harness with CONSULT-II set in "DATA MONITOR (AUTO TRIG)" mode. Check the voltage of the related ECM terminals or monitor the output data from the related sensors with CONSULT-II. See PIN VOLTAGE & PID VALUE CHARTS in PIN VOLTAGE/PID VALUE CHARTS article. The diagnostic procedure contains a description based on open circuit inspection. Inspect the circuit for a short. Repair or replace the malfunction parts. If malfunctioning part cannot be detected, see INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
  7. Once you have repaired the circuit or replaced a component, you need to run the engine in the same conditions and circumstances which resulted in the customer's initial complaint. Perform the DTC confirmation procedure of currently logged DTC and confirm the normal code DTC P0000 is detected. If the incident is still detected in the final check, go to step  6 and use a method different from the previous one. Before returning the vehicle to the customer, be sure to erase the unnecessary (already fixed 1st trip) DTC in ECM. See CLEARING DIAGNOSTIC TROUBLE CODES  .
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